(a) Field of the Invention
The present invention relates to a random access method and a terminal supporting the random access method.
(b) Description of the Related Art
CSMA/CA (Carrier Sense Multiple Access/Collision Avoidance) is used in a wireless local area network (WLAN) (Wireless LAN). CSMA/CA is contention-based medium access control that is simple and is easily implemented, and thus it is widely used in a communication system that uses a broadcasting channel such as a wireless communication.
When many terminals are in a network or a network environment changes over time, such a random access has a drawback that causes a deterioration of performance. For example, a DCF (Distributed Coordination Function) used in the wireless local area network (WLAN) has a drawback that if the number of terminals increases in the network, a collision probability increase between data packets, which deteriorates a data rate. Meanwhile, p-persistent CSMA may be optimized in a given specific network environment, whereas the p-persistent CSMA has a drawback that if the network environment changes, a deterioration of performance occurs.
Another drawback of the conventional random access is that although some of the terminals present in the same network transmit a great amount of data, whereas other terminals may transmit only a remarkably small amount of data. That is, fairness between terminals may not be secured.